Dynamo-electric machine.



' PATENTED DEC. 11, 1906.;

w. STANLEY. v v DYNAMO ELECTRIC MACHINE,

APPLICATION II'LEI) MAY 22; 1905. v

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avwwwto'c mum/v (Sm/Mfr PATENTED DEC. 11, 1906.

. W. STANLEY. DYNAMO ELECTRIC MACHINE.

APPLIOATICH FILED MAY 22, 1906.

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' lmilmeooeo U N ITED. STATE-s PATENT OFFICE.

Specification of Letters Patent.

Patented Dec. 11 1906.

application filed Ma a, 1905. slain in; 261,503.

.To @ZLZDILOT/h it, may con" 37%:

{ 513a it known that I, WILLIAM STANLEY, a

citizen-of the United States, residing at Great ,Barrington, Berkshirecounty,- Massachusetts; have invented certain new and use-, fillImprovements in" DynamoeElectric Ma'- chines, of which-the following isa full, clear.

and exact description.

. My' invention relates to dynamo-electric machines,iand has for itsobject toprovide a self-exciting dynamo-electric machine in which thefield producing windings are ener-i gized by-alternating currentssupplied from the machine itself.

"explained how in certain, machines of the self-exciting rotary fieldtype it is necessary that the phase of the electromotive force i1i-''duced on the stator-windings shall not coin- 'cide with the phase" ofthe electromotive force induced onthe rotor-windings, and I havedescribed various means for accom plishing this result. Such meansconsist'in v placing windings symmetrical in construction indissymmetrical position or inrplacing windings dissymmetrical inconstruction symmetrical positions. I have now discovered means wherebythe necessary displacement of the electromotive forces maybe obtained bywindings which are symmetrical in. con.- struction andalso symmetricalin position,

the difference of phase of the rotor and stator electromotiye forcesbeing brought about'by the introduction of phase-differing electro-'motive forces upon the magnetizing-circuits of the machineThisarrangement is" particularly useful in cases Where it is in certaincases desired to dispense with the commutator or to have the windings ofa large number of; turns of relatively high resistance. Thus in caseswhere dissymmetry of position is relied. upon to'produce thedissymmetricalfield such a high-resistance winding would necessit'atesuch a displacement of the rotor and required end.

stator windings as would lessen their mutual induction and interferewith the inherent regulation of the. machine, which is dependent largelyupon low resistance and high mutual induction between the twocircuitsgMy present invention makes it unnecessary to have 'any displacement ofthe windings, and

therefore preserves the mutual induction be-.

tween the circuits, and thus accomplishes the The followingis adescription of apparatus embodying my invention, reference being had to'the. accompanying drawings, in which- Figure -1 representsdiagrammatically one -arrangement embodying myinvention. Fig.lfrepresentsin detail the winding of the transformer. embodied thereinfiFig. 1 represents a modification of the transformer. F ig. 2 representsanother embodiment of m invention. Fig. 3 represents a third embodimentin which compounding action also is providedfor. Fig. 4 representsanother art rangement'. I 1 In applications already filed by me I have.

Referring more. particularly to the drawings, A represents arotor-winding. B is the commutator, to which this winding is connected.C, D,'E, and F are brushes bearing upon said commutator.

G is the stator-winding. g

is the winding of an exciting-transformer, in the presentinstancerepresented as a rotary field-transformerand shown more fully inFig. 1*, from which taps I, J, K, andv L are taken, these taps beingconnected, re spectively, to the rotor-brushes O, D, E, and

nected at points G D E F" u on the statorwinding directly opposite to te points C, D,

E, and F upon the rotor-winding. Thetaps less the lag of themagnetizing-current of the stator.

minals and one upon the stator-terminals, difiering in phase from oneanother and competent to urge a magnetizin -cu rrent through the rotorand stator wind1ngs,"aiid thus to magnetite the machine. similar resultcan be. obtained with the. exciting-transformer shown in Fig 1 which hastwo-windings constituting distinct priniaryand secondary, I

as distinguishedfrom the single winding of Fig. 1*. When the terminals ij 10 lofthis transformer are connected to the rotorbrushes and theterminals i" j is Z are con-.

nected to the stator-taps, the. angle of dis-. placement of thetransformer-terminals in this case will also be substantially equal toninety degrees less the lag of-the magnetizing currents. v

Instead of using a rotating field-transformer .Other taps I J -K L arealso taken 'from'this transformer-winding and are 'con- -8 .I J K L- andI.J K L are displaced by an angle substantially equal to ninety degreesIn this way two ele'ctromotiveforces are obtained, one upon. therotor-tero I ICC other types of exciting-transformers may be used andmay be arranged 1n various Ways so long as the transformers induceelectro motive forces upon the energizing-circuits of the machine inquadrature to the electrometive forces induced by the rotation of itsrotor, and therefore competent to urge a current over the resistance ofthe magnetizingcircuit. Such an arrangement is shown in Fig. 2, inwhich, as in Fig. l, A is the winding of the rotor. B is the commutator,OD E F the brushes bearing thereon, and G the statorwinding. M is theprimary winding of an exciting-transformer connected across the mains ofone phase, whose secondary M? is connected to the brush (J of the otherphase and to a stator-tap in line therewith. N is the primary of asecond exciting-transformer connected across the mains of the otherphase and having its secondary N connected at one end to the brush D ofthe first phase and at the other end connected to the stator-tap in linetherewith. These transformers are so wound that the inducedelectromotive forces of the transformer secondary windings aresubstantially in quadrature to the induced electromotive forces of therotor and stator windings. When connected as shown, these transformershave induced in their secondary windings electromotive forces which arecompetent to urge currents over the resistances of themagnetizing-circuits, and thus excite the machine.

I11 order that the machine abovedescribed may also compound, I mayprovide compounding primaries for the magnetizingtransformers orcompounding-transformers Whose primaries O O are in series with theWork-circuits, respectively, and whose secondaries O O are in series,respectively,

with the secondaries of the eXciting-trans-' This arrangement resultsm-causformers. ing the energizing-currents to vary with the load uponthe worl -circuits, so that the ma-- chine may be made to have anydesired potential gradient. The particular work-circuit with which aparticular compoundingtransformer should be in series depends uponwhether the machine is to be compounded for a lagging load or a unitypowerfactor load. The arrangement shown in Fig. 3 is the proper one whenthe load is of unitypower factor. In this case, since the workingcurrents lag 0 behind their electromotive forces, the electromotiveforces introduced into the energizing-circuits by thecompounding-transfor111ers will increase with increase of load and willtherefore cause-an increase of magnetizing-current. Thecompounding-transformer, if connected so as to introduce an opposingelectromotive force into the energizing-circuit, will obviously producea regulation resultin in a ne ative potential gradient, while if t e twoe lectromotive forces work together the re result in a positivepotential gra em.

The arrangement of Fig. 4 shows one of each pair of mains connected tothe center of a transformer secondary. Thus in Fig. 4 one of thevertical mains is connected to the center of the secondary winding Minstead of being connected directly to the brush C, as in Fig. 2, whileone Oftheother pair of mains is connected to the center of the secondaryN 4 instead of being connected directly to the brush D, as in Fig. 3.The connections of Fig. 4, With the above exception, are the same asthose of Fig. 2. The arrangement of Fig. 4 is particularly advantageouswhere the conditions are such that both stator and rotor windings aresupplyin substantially equal amounts of enemy to the mains, sinceneutralized for all load-currentsthat is to say, the self-induction ofthe secondaries is neutralized for load-currents flowing from both rotorand stator circuits, since the rents in the two halves of thesecondaries are equal and opposite, and thus neutralize one another.This-arrangement tends to maintain the mutual induction between therotor and stator circuits, because it eliminates a self-induction in thecircuits.

Without desiring to limit myself to the particular arrangements andconnections above described or to the precise form of transformers abovereferred to, since obviously changes will occur to those skilled in theart, what I claim is f 1. In a dynamo-electric machine, the combinationof rotor and stator windings connected to ether, and means external tosaid windings 'or inducing upon the circuits thus formed alternatingelectromotive forces competent to urge alternating magnetizing-currentsthrough them. 2. In a dynamo-electric machine, the come bination ofmultiphase rotor and stator windings connected together, andexciting-transformers having their secondaries in the connection betweensaid windings.

3. In a dynamo-electric machine, the combination of rotor and statorwindings connected together and to work-circuits, andexciting-transformers having their secondaries in the connection betweensaid windings.

4. In a dynamo-electric machine, the combination of multiphase rotor andstator windings connected together, multiphase mains leading from suchconnections, and excitingtransformers having their primaries in paral--lel with the mains of one phase and their see- I 'ondaries in seriesconnection with said wind mgs.

5. In a dynamo-electric machine, the combination of rotor and statorwindings, a con;

nection between said windings and to a workthe self-induction of thesecondaries is thus lation will 0 5 magnetizing forces set up by theload-cur nection between said windings, and means for inducingalternating electromotive forces in such connection competent to urgealter-'- nating magnetizing-currents in the same relative directionthrough said windings.

7. In a dynamo-electric machine, the combination of rotor and statorwindings 'connected together, with transformers for inducing alternatingmagnetizing-currents within such windings whereby a rotating magneticfield is produced, which with rotation induces opposing electromotiveforces of the same phase and similar frequency upon said connectedwindings.

8. In a dynamo-electric machine, the combination of rotor and statorwindings connected together andzto a work-circuit, withexciting-transformers so connected to said windings as to inducemultiphase magnetizing-currents in them whereby a rotating magneticfield is produced, and means for delivering energy-currents from both ofsaid windings to the external circuits.

9. In a dynamo-electric machine, the combination of multiphaserotor-windings and multiphase stator windings, multiphase mains leadingfrom said windings, connections between both of said windings, and aprimary having windings in said connections and connected to said mains.

10. In a dynamo-electric machine, the combination of rot0rwindi-ngs andstatorwindings, a commutator connected to said rotor-windings, brushesconnected to said commutator and connected to said statorwindings, andexciting-transformers having their secondaries in the connection betweensaid brushes, the brushes to which the primaries are connected beingangularly displaced relatively to the brushes to which the secondariesare connected, and said statorwindings and theirprimaries connected tosaid brushes.

11. In a dynamo-electric machine, the combination, of rotor and statorwindings connected together, means for inducing upon the circuit thusformed electromotive forces competent to urge magnetizing currentsthrough them, and means for varying the value of such electromotiveforces in propor-.

tion to the variation of the'load of the machine.

12. In a dynamo-electric machine, the combination of rotor-windings andstatorwindings, a commutator connected to said rotor-windings, brushesbearing upon said commutator, connections between' said brushes and saidstator-windings, secondary windings of exciting-transformers in saidconnections and compounding-transf0rnrers having their primaries inseries with the workcircuits and their'secondaries in series with saidsecondary windings.

13. In a dynamo-electric machine, the combination of rotor-windings andstatorwindings, a commutator connected to said rotor-windings, brushesbearing upon said commutator, connections between said brushes andpoints on said stator-windings directly opposite said brushes, and meansinserted in said connections for producing electromotive forcescompetent to urge magnetizing-currents over said stator-windings.

14. In a dynamo-electric machine, the combination of rotor-windings andstatorwindings, a commutator connected to said rotor-windings, brushesbearing upon said commutator, connections between said brushes andpoints on said stator-windings substantially opposite saidbrushes,transformers in said connections producing secondaryelectromotive forcescompetent to urge magnetizing-currents over'said statorwindings, andcompounding-transformers having their secondaries-also in saidconnections and their primaries in series with the work-circuits.

15. In a dynamo-electric machine, the

combination of rotor-windings and statorwindings, a commutator connectedto'said rotor-windings, a plurality of brushes bearing upon saidcommutator, and excitingtransformers each having its primary con nectedto one pair of brushes and its secondary' connected to saidstator-windings at points such as to setup a magnetic field actingdynamically upon the circuit connecting a pair of brushes otherthan-that to which it is connected.

' WILLIAM STANLEY. Witnesses:

E. FACOIOLY,

JOSEPH C. FREIN.

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